Melting furnace



Jan. 23, 1940. J. J. MADER NELTING' FURNACE Original Filed Jan. 3. 1935 4 INVENTOR. JoH/v JI/Wa ale r M ATTO-RNEY Reissued 1e. 23, 1940 UNITED STATES MELTIN G FURNACE John J. Mader, Parma, Ohio, assignor to The Apex Electrical Manufacturing Company, Cleveland, Ohio,a corporation of Ohio Original No. 2,074,115, dated March 16,1937, Se-

rial No.-256, January 3, 1935.. Application for reissue November 3, 1939, Serial No. 302,751

8 Claims. (01. 266. 33)

This invention relates to improvements in melting furnaces and in particular furnaces used for melting non-ferrous metals and their alloys in connection with die casting or permanent molding apparatus.

One of the objects of this invention is to provide a melting furnace having a chamber with a working opening by way of which to ladle or otherwise remove molten metal in which substantially all slag or dross has been removed from the surface of the metal prior to its admission to such chamber.

Another object of the invention is to provide a melting furnace arranged to permit several workmen to safely and simultaneously remove molten metal from the furnace without interfering with each other whereby several molds may be efficiently operated at the same time with metal supplied from a single furnace.

Another object of the invention is to provide a melting furnace in which the dross or other impurities of the metal are confined to one chamber orlocality in the furnace from which it may be easily and readily removed without interference to the withdrawal of metal from the furnace.

Another object of the invention is to provide a melting furnace of. high efiiciency in which there is a great saving in fuel consumption.

.Another object of the invention is to provide a melting furnace constructed in such a manner that parts which are most subjected to deterioration or wear may be easily repaired or replaced.

A further object of the invention is to provide a melting furnace which is relatively inexpensive both to construct and to keep in repair.

With these and other objects in view, the invention consists in the novel construction, arrangement and combination of parts, hereinafter illustrated and described in some of its embodiments in the accompanying drawing and particularly pointed out in the appended claims.

In the drawing accompanying and forming a part of this specification, Figure 1 is a side elevational view of the rear of a furnace illustrative of the invention; Figure 2 is a detail sectional view of the furnace with certain of the parts broken away for the purpose of showing the charging opening of the furnace; Figure 3 is a fragmentary plan view of part of the top of the furnace; Figure 4 is a detail sectional view simiof one end lar to Figure 2 illustrating the charging device of the furnace; Figure 5 is a detail sectional view taken on line 5-5 of Figure 4; and Figure 6 is an end elevational view, of the charging chute.

The furnace disclosed herein for purpose of illustrating one mode of practicing this invention is indicated generally by the numeral I and it is in the form of a hollow, closed structure having a material charging opening atthe rear thereof defined by a rectangular frame 2 at the bottom of which is located a ledge or sill extending away from the furnace and terminating in a down-turned edge or lip 3. The frame 2, which is subjected to considerable wear in the use. of the furnace, is detachably secured to the furnace by bolts 4 so that when worn out it may be readily removed and replaced by a new frame.

nHeat may be supplied to the interior of the furnace by means of a fluid fuel burner 5, or if desired, electrical heaters (not shown) could be used as well, particularly in localities where the cost of electrical power compares favorably with gas and fuel oils. The heated gases may be vented from the interior of the furnace by way of a flue 6, controlled by a damper I having operating arms and cords or chains 8 and 5 respectively, by means of which the damper may be manipulated.

Pivoted ,catches l0 and II are provided for holding the lids l3 and M respectively, in an up right or open position with respect to certain openings in the furnace which they are arranged to cover. These lids are pivoted at l5 and it respectively, at one side of the openings formed in the apertured top .plates I1 and i8 respectively, and they are preferably lined with a refractory heat insulating material so as to reduce the transfer of heat therethrough.

Ladling or dipping chambers 20 and 28 of similar construction are provided at the opposite ends of the furnace for the ladling of. molten metal out of the furnace. The chamber 20 is formed by an outer wall I! and a bottom wall 23 of heavy gauge sheet metal having refractory linings II and 22, the former of which is in contact with the molten metal in the furnace. Ac-

. cess to the chamber 20 is had by way of the aperture provided in the top plate l8 when its lid II is in its open position.

The chamber 20 communicates with the main or melting chamber 26 of the furnace by means of an aperture or passageway 24 located at th lower level of the furnace with its top ldbated at a r considerable distance below the level of the mo]- ten metal in the furnace. By reason of this arrangement, heated ,gases and impurities in the form of dross and slag floating on the metal are retained in the main chamber of the furnace,

which issupplied with of the Q A dipping chamber 28 and communicating pasend of the furnace.

'sageway 21 similar to those just described for one end of the furnace. are provided at the other The floor of themain V 'gchamber I6 is slanted downwardly in a direction towards the front of the furnace so as to permit molten metal to flow continuously away from the charging endof the furnace to its point of removalat the chambers and 28.

r The chamber 28 is formed by a bottom mun andside walls 3| of sheet metal with refractory linings 30 and 10* similar to the linings 2| and 1110f the chamber 20; The apertured top plate I! andlid l3 of the chamber 28 are'also substantially identical with the plate It! and lid ll of the chamber 20. and: bottom 32" of the melting chamber 25' too are formed from heavy gauge sheet. metal with refractory linings 33 and 33, the former beingexposed to the molten metal and-gases in the compartment 26.

As shown best in Flgure'2, the sides 32 An inclined chute having side walls 3| and :5

l and abottom 36 is provided for discharging materials into the melting chamber 26 by way of the'opening defined by the frame 2. The side is'lower than the side 34 so as to facilitate the operation of shoveling onto the chute materials to be fed to the furnace. Ribs 31 define a channel br guideway at the underside of the chute for reception of a support carried at one end of the rods-J0 and 4l, the other ends of which are "pivoted from brackets 42 and 43 carried by the 1 rearwall of the furnace.

Aligned holes are provided in the support 45 and channels 3 for reception of a removable lockingpin or rod, which serves to hold the.

chutein the full-line position shown in Figure 4.

Upon removal'of the pin '38 the chute may be shifted to the broken line position shown in Figland held in such positionby inserting the pin 38 in the holes}! of thechannelmembers 31 andthe hclesprovided for its reception in'the support 45,.wheleupon the, chute may be swung to one side of the opening of the frame 2 and the slag and dross may be skimmed from the surface of'the metalin the melting chamber 26 and raked up thej inclined edge of the wall {I overf the projecting lip 3 beneath which a-container (not shown) may be placed rm the m as itis removedifrom the In the operation of furnace.

a m, serve to new to be chflacdinto {when momma metal isied-to time, a

great deal of-smoke and gases which .maybewithdrawn metal 'tobe' fed into thedamperlbymeanscfthearmsl'andcordsi. Itwillthusbeseen that in theuseofthisfurnace, heat which is ordinarily 'wastedis utilized to preheat and at least the me! reamed by reasonfofnavm a working. or

@for theremoval of mammalian to heatlmesofonemrnaceandtheuse cfonlyoneburnen un n 'r;

connecting the melting chamber with the dipping chambers. are located sumciently below the top level of themolten metal so as to permit clean metal only to flow into thedipping chambers and the dross and slag which floats to the top of the metal-in the melting chamber will be retained therein. By reason of having only clean metal in the dipping chambers, the metal may be removed by ladling without requiring even infrequent skimming. In permanent molding or in a 'die casting process; it is particularly objection- 'able to have, any dross'or other impurities get into the mold or die which will result in imperfect castings.

By reason-cf the provision of a plurality of working openings for the furnace, it is possible to efliciently operate several molding devices, and

the attendants for each device will have ample room in which to work so that accidental spilling of molten" metal through interference between workmen vwill be minimized. The rounded cornets of theouter jackets of the dipping chain bers reduce the danger of the clothing of the attendants being caught on the furnace.

The furnace disclosed herein is shown as having 'two separate openings from which molten metal may beremoved. Itis within the contemplation openings to three or more ifdesired. By using a sheet metalouter casing such as shown, additional working openings may be easily added to facilitatesthe installationof the refractory lining and by usa'of a double lining, the cost of upkeep of thefurnace. is greatly reduced as the inner lining only ordinarily is subject to wear and replacement. It is preferred to form the inner lining of the furnace from a refractory brick of the invention to increase the number of such the furnace. The use of a sheet metal casing also K capable-of withstanding the treatment to which.

it is subjected to in the use of the furnace and the lining between the refractory brick and the sheet s'teelfwalls of the furnace is preferably formed home ground or powdered refractory material which may be'composed of ganister and powdered asbestos so that the lining provides a cushioned backing for the refractory brickwork whereby such brickwork is not subjected to strains due to the thermal expansion and contracv tionin the different parts of the furnace.

- Another feature" of this furnacewhich tends to increase its operating efficiency is that of having the burneri arrangedso as'to dir'ectits flame againsta wall of the furnace at a point some distance'from the' dipping chambers 2| and I. so that the-walls common to the melting and the dipping-chambers are at a lower temperature than some of the other walls of the furnace with the furnace arranged in this manner it is possible to maintain relatively high temperatures in certain portions of the melting chamber to insure the rapid melt ng of the materials therein while at the same time maintaining the temperature of the materials in the melting chamber at a proper temperature for molding operations, which temperature somewhat lower than the temperature considered best for the rapid melting of the metal. v

By referring to Figure 1, it will beseen that Y the" sections the dipping chambers 20 and 2!; the section defining the lower part of the melting chamber II; and the section thereabove which defines theco'mbustion chamber ofthe mrnace. These sheet may.

- the sheet .metal casing of the furnace is formed from four different main sections which include o" V cases if desired, be secured together in a detachable manner by means of bolts (not shown) and it is also within the contemplation of this invention to detachably secure the top plates [1 and I8 of the dippin chambers in a similar manner.

This arrangement greatly facilitates repair work in the diflerent portions 'of the furnace by reason of the fact that different sections of the furnace may be removed one from the other.

Furthermore, it is to be understood that the particular forms ofmelting furnace shown and described, and the particular procedure set forth are presented for purposesof explanation and that various modifications of said apparatus and procedure may be made without departure from this invention as described in the appended claims.

Having thus described my invention, what I claim is:

1. A metal melting furnace for non-ferrous metals having a melting chamber, means for supplying heat to said chamber including a burner adapted to impinge a flame against a wall of the melting chamber, said furnace having an opening located in a wall opposite to the first-named wall ofthe melting chamber for the supplying of metal to the melting chamber, and means for supporting a supply of metal to be fed to the furnace in a position adjacent to the stated opening so that such metal is subjected to radiant heat from the interior of the furnace.

2. A metal melting furnace for non-ferrous metals having a melting chamber, means for sup- 7 plying heat to said chamber including aburner for supporting a supply adapted to impinge a flame against a wall of the melting chamber, said furnace having an opening located in a wall opposite to the firstnamed wall of the melting chamber for the supplying of metal to the melting chamber, means of metal to be fed to the furnace adjacent to the stated opening comprising an inclined chute discharging into the said furnace opening, arranged so' that such metal is subjected to radiant heat from the interior of the furnace.

3. A melting furnacefor non-eferrous metals having a melting chamber in the form of sheet metal outer casing with an inner refractory lining, means for supplying heat to said chamber,

a frame-work defining a metal charging opening with a shelf extending away from the furnace and terminating in a down-turned lip detachably secured to a side of the furnace, and a displaceabie chute at the side of the furnace inclined usoastodischarleintolaidopening.

4. A metal melting furnace for nonferrous metals having a melting chamber, means for supplying heat to said chamber including a burner adapted to impinge a flame against a wall of the melting chamber, said furnace having an opening located in a wall opposite to the firstnamed wall of the melting chamber for the supplying of metal to the melting chamber, means for supporting a supply of metal to be fed to the furnace adjacent to the stated opening comprising a chute adapted for holding said supply of metal in position where it is exposed to the radiant heat generated in the melting chamber of the furnace.

5. A metal melting furnace having a melting chamber with an opening for supplying metal to the melting chamber, means for supplying heat to said chamber, and means pivoted to the furnace for holding a supply of metal to be fed to the furnace in a position adjacent to the stated opening thereofwhich it is subjected to the heat generated by the furnace, said last-named means being adapted to be swung away from such open- V ing to permit better access thereto.

6. A metal melting furnace having a melting chamber, means for supplying heat to said cham-' ber, and means for feeding metal to said chamber comprising an opening in the furnace, a

chute adjacent to said opening and a support therefor pivoted for movement about a vertical axis and slidably supporting said chute.

7. A metal melting furnace for non-ferrous metals having a melting chamber, means for supplying heat to said chamber including a burner adapted to impinge a flame against a wall of the melting chamber, said furnace having an opening located in a wall opposite to the firstdetachably associated units having generally rectangular cross-sectional areas, one of such units defining the top and upper sidewalls of the melting chamber of the furnace, another of such units defining a dipping chamber alongside of and communicating with the melting chamber.

Jorm J. manna. 

